Category Archives: sample handling

Handling Powder Samples for DSC Runs

There are powdery materials such as finely ground polymers, polymer microspheres and active pharmaceutical ingredients (APIs) that may require DSC analysis and characterization.  Powder samples can be difficult to pack into DSC pans especially if they are static or low bulk density.  It could be a messy business with jumpy powders where they cling to your spatula and both inside and outside of the DSC pan.  Low bulk density prohibits the sample to have good contact with the bottom of the DSC pan.  And if small transitions are of importance where a large sample amount is needed, low bulk density also makes it difficult to pack more powders in a pan.

One way to overcome these difficulties from a powdery material is to make it into a pellet.  A pallet with its diameter slightly smaller than your DSC pan will enable you to pack a larger amount of sample into the pan with much improved surface contact and with no static issues.  All you need is a pellet maker with the correct diameter, about 3/16” to fit into most DSC pans.  If you work in an analytical lab and happen to have a KBr pellet maker (traditionally used for FTIR), I find it to be an excellent pellet maker for this purpose.